/*
 * Created on Apr 30, 2004
 * Created by Alon Rohter
 * Copyright (C) Azureus Software, Inc, All Rights Reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 *
 */

package com.aelitis.azureus.core.peermanager.messaging.bittorrent;

import org.gudy.azureus2.core3.util.DirectByteBuffer;
import org.gudy.azureus2.core3.util.DirectByteBufferPool;

import com.aelitis.azureus.core.networkmanager.RawMessage;
import com.aelitis.azureus.core.peermanager.messaging.Message;
import com.aelitis.azureus.core.peermanager.messaging.MessageException;

/**
 * BitTorrent keep-alive message.
 */
public class BTKeepAlive implements BTMessage, RawMessage {
    private byte version;
    private DirectByteBuffer[] buffer = null;

    private boolean no_delay = false;

    public BTKeepAlive(byte _version) {
        version = _version;
    }

    // message
    public String getID() {
        return BTMessage.ID_BT_KEEP_ALIVE;
    }

    public byte[] getIDBytes() {
        return BTMessage.ID_BT_KEEP_ALIVE_BYTES;
    }

    public String getFeatureID() {
        return BTMessage.BT_FEATURE_ID;
    }

    public int getFeatureSubID() {
        return BTMessage.SUBID_BT_KEEP_ALIVE;
    }

    public int getType() {
        return Message.TYPE_PROTOCOL_PAYLOAD;
    }

    public byte getVersion() {
        return version;
    };

    public String getDescription() {
        return BTMessage.ID_BT_KEEP_ALIVE;
    }

    public DirectByteBuffer[] getData() {
        return new DirectByteBuffer[] {};
    }

    public Message deserialize(DirectByteBuffer data, byte version) throws MessageException {
        if (data != null && data.hasRemaining(DirectByteBuffer.SS_MSG)) {
            throw new MessageException("[" + getID() + "] decode error: payload not empty");
        }

        if (data != null)
            data.returnToPool();

        return new BTKeepAlive(version);
    }

    // raw message
    public DirectByteBuffer[] getRawData() {
        if (buffer == null) {
            DirectByteBuffer dbb = DirectByteBufferPool.getBuffer(DirectByteBuffer.AL_MSG_BT_KEEPALIVE, 4);
            dbb.putInt(DirectByteBuffer.SS_BT, 0);
            dbb.flip(DirectByteBuffer.SS_BT);
            buffer = new DirectByteBuffer[] { dbb };
        }

        return buffer;
    }

    public int getPriority() {
        return RawMessage.PRIORITY_LOW;
    }

    public boolean isNoDelay() {
        return no_delay;
    }

    public void setNoDelay() {
        no_delay = true;
    }

    public Message[] messagesToRemove() {
        return null;
    }

    public void destroy() {
        if (buffer != null) {
            buffer[0].returnToPool();
        }
    }

    public Message getBaseMessage() {
        return this;
    }

}
